86 CRETACEOUS LAMELTJBRANCHIA. 



Surface of valves siiiootli exce])t for growth-i'idges, of wliicli the curved portions 

 near the dorsal margin are more distinct than the other jjortions. 



Hinge with small transverse teeth at the anterior end and six or seven long 

 narrow obli(|ue teeth near the posterior entl — the latter decreasing m length 

 posteriorly. 



Measurements .- 



(I) (2) (3) (4) 



Height' . 31 . 24 . 15 . 8 mm. 

 Length- . 182 . 125 . 71 . 35 „ 

 (1—4) Gault, Folkestone. 



Affinities. — This species belongs to Freeh's ■' ' Group of (irrrillid solejmidi'i:;.' 



The only locahties given for G. Forhesiana by d'Orbigny ai-(j Shanklin and 

 Athcrfield, and apparently liis figured sj^ecimen came from the latter place. All 

 the examples from Shanklin are in the form of casts of which the posterior part is 

 usually missing; it is consequently difficult to make out their real charactei'S, but 

 they probably belong to this species. 



The examples found in the Gault and Upper Greensand differ somewhat from 

 the specimen figured by d'Orbigny. In the former the shell is less slender and 

 tapers more quickly posteriorly ; the posterior ear, however, agrees with d'Orbigny's 

 figure. 



A considerable number of examples of Grrvillin from different localities and 

 horizons have been referred by various writers ' to G. solenoides, Defrance,^ but 

 without seeing a large collection of those forms it is impossible to determine their 

 relationship to one another and to the examples here described. The figures given 

 l)y Defrance do not enable us to form a satisfactory idea of the characters of the 

 species; in his original account (1820) he gave " He d'Aix" as the locality, but in 

 his later remarks (1824) he states that the specimens came from the department 

 of Le Manche. 



The Senonian specimens figured by d'Orbigny' as (/. iii-iri(loiiJcs (noii G. 



' From posterior end of liiu^-e-liuo to opposite margin of valve. 

 - From umbo to posterior extremity. 



* 'Ceutralb. fiir Miu.,' etc. (1902), p. G15. 



* Sowerby (18-20), Goldfuss (183(J), Iteuss (184(j), Midler (1847), d'Orbiguy (1847), .\ltli (18,50), 

 Zittel (1866), Favre (1869), StoUczka (1871), Geiuitz (1873), Brauus (1876), Fritscb (1877-93), 

 Niitling (1885), Griepeukerl (1889), Holzapfel (1889), Liiudgreu (1894), Vogel (1895), Midler (1898), 

 G. oblonga, Bohm (1885). 



5 'Diet. Sci. nat.,' vol. xviii (1820), p. 503; vol. xxxii (1824), p. 316, pi. Ixxxvi, fig. 6. 



« 'Pal. Fran^. Terr. Crct.,' vol. iii (1846), p. 489, pi. cccxcvii, fig. 2 (aud perhaps fig. 1). Prof. 

 M. Boule informs me that the original of fig. 1 cannot be found in the d'Orbiguy collection, aud that 

 the original of fig. 2 comes from Valogues (Manche). 



